30 

 SOME REMARKS UPON LIMOSELLA 



By Francis W. Penxell 



Professor Fernald's interesting discussion of our eastern coastal 

 species of LinioseUa reached me as I was on the point of taking 

 up the same problem. I had suspected, and had tentatively so 

 marked it in my notes, that our eastern species would prove 

 distinct from L. tenuifoUa Wolf of Europe, and should be called 

 L. subulatu Ives. That it was specifically distinct from the plant 

 of the Rocky Mountains I was certain, having studied and made 

 descriptions of both in their native environments. 



My notes, made from living plants and supplemented by 

 herbarium study, show the following contrast between Limosella 

 aquatica of the Central Rockies and nearby plains and L. suhiilata 

 of the Atlantic seaboard : 



L. aquatica. — Corolla about 2 mm. wide; lobes somewhat 

 spreading, acute or acutish, dull-white. Anthers about i mm. 

 long, purplish. Capsules 2.5-3.2 mm. long, borne on spreading 

 pedicels. Seeds .5 mm. long, dull amber-brown, about 6-7 

 ridged, relatively coarsely transverse-lined. Calyx-lobes uni- 

 form. Leaves about 3 cm. long, consisting of a petiole and a 

 more or less dilated lanceolate blade about i cm. long. Plant 

 rosulate, 10-20 leaved, surrounded by numerous radiating few- 

 jointed stolons. 



L. snhulata. — Corolla about 3 mm. wide; lobes widely spread- 

 ing, obtuse, white, tinged with lavender-blue. Anthers about 

 2 mm. long, dark purple-blue. Capsules 2-2.3 rnm. long, borne 

 on arcuately decurved pedicels. Seeds .6-.7 mm. long, bright 

 amber-brown, about 8-9 ridged, more finely transverse-lined. 

 Calyx-lobes upcurved, in fruit the tube tending to split on the 

 anterior side. Leaves 1.5-2 cm. long, nearly filiform, terete, 

 obtuse. Plant chain-like, consisting of plantlets borne on joints 

 of extensively creeping filiform stolons, each plantlet usually 

 5-10 leaved. 



In agreement with Professor Fernald, I am unable to distin- 

 guish the plant of the Rockies from that of Eurasia. The 

 western plant sometimes has pinkish corollas, but, so far as I can 



